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2,6-TOLUENE-DIISOCYANATE (TDI)
| CAS # | 91-08-7 | 
|---|---|
| Formula | 
                              
 C₉H₆N₂O₂  | 
          
| Synonyms | 
                              
 2,6-toluene diisocyanate; 2,6-TDI; 2,6-diisocyanato-1-methylbenzene; 2,6-diisocyanatotoluene  | 
          
| Physical description | Colorless to pale-yellow solid or liquid with a pungent odor. | ||
|---|---|---|---|
| Boiling point | 264-271°F | Molecular weight | 174.2 | 
| Freezing point/melting point | 68-72°F | Vapor pressure | 0.5 mmHg at 77°F for 80% 2,4:20%; 2,6 TDI mixture | 
| Flash point | Vapor density | 6 | |
| Specific gravity | 1.2244 at 68°F | Ionization potential | |
| Lower explosive limit (LEL) | 0.9% | Upper explosive limit (UEL) | 9.5% | 
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | T177 | 
|---|---|
| Sampling group | |
| Sampler/Sampling media | Isocyanate Sampling Filter Kit - GFF (37 mm, open-faced) coated with 1 mg 1-(2-pyridyl)piperazine [SLTC103] | 
| Sampling time* | 
 15 min  | 
                                    
| Sampling volume (TWA)* | 
 15 L  | 
                                    
| Sampling flow rate (TWA)* | 
 1 L/min  | 
                                    
| Sampling volume (STEL/Peak/C)* | 
 
  | 
                                    
| Sampling flow rate (STEL/Peak/C)* | 
 
  | 
                                    
| Analytical method instruments | UHPLC | 
| Method reference | OSHA 5002 (fully validated) | 
| Notes | 
 Refrigerate coated filters until used. Sample open-faced!!  | 
                                    
| Special requirements | 
 
  | 
                                    
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media | 
 
  | 
                      
|---|---|
| Bulk Method | 
 
  | 
                      
| Device | Detector tube | Hazard Assessment Test Kit for Aromatic Isocyanates | 
|---|---|---|
| Model/Type | Dräger - Toluene diisocyanate 0.02/a, 6724501 | 769-1002 | 
| 
                              Sampling information  (see manufacturer instructions)  | 
                                      25 strokes, approx 0.02-0.2 ppm range, uncertainty 30% | Isocyanate Surface and Dermal Sampling, Hazard Assessment Test Kit for Aromatic Isocyanates | 
| 
               
                                  OSHA PEL 
            8-hour TWA (ST) STEL (C) Ceiling Peak  | 
            
               
                                  NIOSH REL 
            Up to 10-hour TWA (ST) STEL (C) Ceiling  | 
            
               
                                  ACGIH TLV© 
            8-hour TWA (ST) STEL (C) Ceiling  | 
            |||||
|---|---|---|---|---|---|---|---|
| PEL-TWA | 
                              
 
  | 
            REL-TWA | 
                              
 
  | 
            TLV-TWA | 
                              
 0.001 ppm (inhalable fraction and vapor) [2015]  | 
            PEL-TWA | 
                              
 
  | 
          
| PEL-STEL | 
                              
 
  | 
            REL-STEL | 
                              
 
  | 
            TLV-STEL | 
                              
 0.005 ppm (inhalable fraction and vapor) [2015]  | 
            PEL-STEL | 
                              
 
  | 
          
| PEL-C | 
                              
 
  | 
            REL-C | 
                              
 
  | 
            TLV-C | 
                              
 
  | 
            PEL-C | 
                              
 
  | 
          
| Skin notation | 
                              
 NA  | 
            Skin notation | 
                              
 NA  | 
            Skin notation | 
                              
 Y  | 
            Skin notation | 
                              
 NA  | 
          
| Notes: | 
              Notes: 
              
 Not established  | 
            
                              Notes: 
                                            
 dermal sensitizer (DSEN), respiratory sensitizer (RSEN)  | 
            
                              Notes: 
                                            
 Not established  | 
          ||||
| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: IARC-2B, NIOSH-Ca, NTP-R | 
                              Notes:
                                            
 
  | 
            ||||||
| 
                              
                  AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
                
                                            
 0.01 ppm/0.15 ppm/0.6 ppm  | 
          |||||||
Additional Resources and Literature References
| 
               NOAA: CAMEO Chemicals - Toluene-2,6-diisocyanate NIOSH: Pocket Guide to Chemical Hazards - Toluene-2,6-diisocyanate Literature References 
  | 
          
Last Updated Date : 04/02/2025